• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.296-298
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• 2007

Two lignan glycoside compounds were isolated from the twigs of Vaccinium oldhami (Ericaceae) through repeated column chromatography. Their chemical structures were elucidated as lyoniside and ssioriside, respectively, by spectroscopic analysis.

• Journal of The Korean Astronomical Society
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• v.54 no.3
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• pp.89-102
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• 2021

Even in an era where 8-meter class telescopes are common, small telescopes are considered very valuable research facilities since they are available for rapid follow-up or long term monitoring observations. To maximize the usefulness of small telescopes in Korea, we established the SomangNet, a network of 0.4-1.0 m class optical telescopes operated by Korean institutions, in 2020. Here, we give an overview of the project, describing the current participating telescopes, its scientific scope and operation mode, and the prospects for future activities. SomangNet currently includes 10 telescopes that are located in Australia, USA, and Chile as well as in Korea. The operation of many of these telescopes currently relies on operators, and we plan to upgrade them for remote or robotic operation. The latest SomangNet science projects include monitoring and follow-up observational studies of galaxies, supernovae, active galactic nuclei, symbiotic stars, solar system objects, neutrino/gravitational-wave sources, and exoplanets.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.155-155
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• 2009

• Journal of Ginseng Research
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• v.36 no.3
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• pp.270-276
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• 2012

The effect of orally administered sun ginseng (SG), which is a ginseng processed by steaming, was examined in adenine-induced chronic renal failure rat. SG significantly decreased both blood urea nitrogen and serum creatinine levels, indicating an improvement of renal function. Also, SG significantly increased the urinary excretion of both urea and creatinine. Furthermore it lowered the blood pressure, and inhibited adenine-induced kidney hypertrophy and edema. Based on these findings, SG may ameliorate chronic renal failures.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.169-171
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• 2005

The methanolic extract of the aerial parts of Persicaria thunbergii was found to show inhibitory activity on Farnesyl Protein Transferase (FPTase). Bioassay-guided fractionation of the methanolic extract resulted in the isolation of isorhamnetin, as an inhibitor on FPTase. This compound inhibited FPTase activity in a dose-dependent manner, and the $IC_{50}$ value of isorhamnetin was $37.5\;{\mu}M$.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1401-1404
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• 2012

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.79.1-79.1
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• 2019

The Schwarzchild-Chang telescope is a confocal off-axis two mirror telescope with D = 50 mm, F = 100 mm and FOV = 8 ° × 8 °. Unlike common off-axis telescopes, the mirrors of the Schwarzchild-Chang telescope share their focal points to remove the linear astigmatism. In this poster, we show the alignment process of the Schwarzchild-Chang telescope with wavefront measurement and the sensitivity table method. Wavefront is measured using the Shack-Hartmann sensor, and Zernike polynomials are obtained from measured wavefront. Sensitivity table method is to calculate alignment errors from the Zernike coefficients. As a result, we evaluate tilt, decenter, and despace of each mirror of linear astigmatism-free con-focal off-axis system.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.47.1-47.1
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• 2019

We report the design and vibration analysis for the optomechanical structures of Linear Astigmatism Free - Three Mirror System (LAF-TMS). LAF-TMS is the linear astigmatism free off-axis wide-field telescope with D = 150 mm, F/3.3, and FOV = 5.51° × 4.13°. The whole structure consists of four optomechanical modules. It can accurately mount mirrors and also can survive from vibration environments. The Mass Acceleration Curve (MAC) is adapted to the quasi-static analysis. Modal, harmonic, and random vibration analysis have been performed under the qualification level of the launch system. We evaluate the final results in terms of von Mises stress and Margin of Safety (MoS).

• International Journal of Oral Biology
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• v.43 no.2
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• pp.53-59
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• 2018

In order to understand biological phenomena accurately, single molecule techniques using a physical research approach to molecular interactions have been developed, and are now widely being used to study complex biological processes. In this review, we discuss some of the single molecule methods which are composed of two major parts: single molecule spectroscopy and manipulation. In particular, we explain how these techniques work and introduce the current research which uses them. Finally, we present the oral biology research using the single molecule methods.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.556-559
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• 2007

Effects of carbon nanotube (CNT) on the in-plain switching (IPS) and fringe-field switching (FFS) modes were investigated. The studies show that the CNT-doped LC cells exhibit lower transmittance but faster response time than those in the pure LC cell. Interestingly, the CNT-doped IPS and FFS modes show different characteristic in effects of operating voltage.